浅埋大断面高速公路隧道下穿国道稳定性分析OA

Based on Xifeng Tunnel,a three-dimensional finite element model was established to quantify the surrounding rock stability of the shallow tunnel with large section under different buried depths and without vehicles,and the dynamic decay rule and dynamic response under different axle loads were studied.The research results show that the vertical displacement of the tunnel surrounding rock presents an"inverted bimodal"curve under different burial depths,and the vertical displacement reaches its maximum value at 2 m from the arch top.With the in-creasing of burial depth,the bimodal shape is gradually obvious,and the vertical displacement of the tunnel surrounding rock continues to in-crease.Under the action of vehicle load,the dynamic noise of rock mass in tunnel decreases continuously in the vertical direction.The sur-rounding rock of the tunnel is most affected by vehicle load at the arch of the guide tunnel on both sides,where the dynamic response of vehicle load is the largest,and the vertical displacement of the surrounding rock of the tunnel increases with the increase of vehicle axle load.